Hollywood was built by selling us happily-ever-afters that can’t even be bought in real-life. Boy gets girl, prostitutes become princesses and the bully always apologizes. But that’s not Jason Reitman’s style. In this uncomfortable, downbeat and dark feature that’s littered with life lessons never learned, Young Adult visits a theme Reitman explored in both Up in the Air and Juno – characters who’ve committed themselves to one distinct identity, and cling onto it like a life-raft when their self-preserving bubble begins to crack.

Mavis Gary(Charlize Theron) is a depressing but very human combination of beauty, insecurity, arrogance, loneliness, entitlement, a drinking problem – and above all, self-protecting delusion. When her marriage fails, this fame-obsessed ghost writer returns home, expecting her humble “hick” town to throw a welcoming parade, and her highschool boyfriend to throw himself at her. Instead, she finds that everyone has moved on – the town has shopping malls and a KenTacoHut, and her old beau has a wife and new baby.

More a slow-burning character documentary than an entertaining, arc-driven story, Theron is remarkable in the ugliest role she’s played since Monster (only figuratively though, so less chance for an Oscar.) Mavis’ attempts to rekindle her romance with Buddy (Patrick Wilson) are an increasingly excruciating exercise in embarrassing ego-trips, and her complete disregard for anyone but herself makes Mavis almost hateful. But tiny details, such as her lonely nights spent watching shows about wannabe celebrities and a hair-pulling habit betray a desperate desire for validation.

Which sadly, she sometimes gets, as awful but attractive people are wont to do. Patton Oswalt shines as a vulnerable former classmate of Mavis who becomes her only confidante during her trip. Despite recognizing her cruelty and narcissism, he can’t help but be drawn to her, and in one of the most heart-wrenchingly honest lines ever uttered, sadly admits that “Guys like me are born loving girls like you.”

An slow, unnerving, unflinching and thought-provoking character study, Reitman’s film expresses an unpopular idea: that it’s almost impossible to go against your essential nature, and most people don’t try. And just like crash-dieters, those who do often quickly revert to their starting shape. And live unhappily ever after.